The invention relates to a hybrid vehicle with at least one drive axle, which can be driven by means of a drive device, which drive device has an accumulator, an electric machine coupled with the accumulator for exchanging electric energy, and an internal combustion engine, which in an active state mechanically drives the electric machine for generating electric energy, and with a control unit which controls the electric machine and the internal combustion engine. The invention also relates to a method for operating a vehicle that can be driven by means of an electric machine as well as with an internal combustion engine, wherein the electric machine and an accumulator of the hybrid vehicle are electrically coupled to each other for exchanging electric energy and wherein the electric machine in an active state of the internal combustion engine is mechanically driven by the internal combustion engine so that the electric machine generates electric energy.
Generic hybrid vehicles with drive devices and methods for operating the drive device are generally known in the state of the art, which thus does not have to be further exemplified in the form of specific references. Hybrid vehicles are vehicles of the general type, also referred to as motor vehicles, and serve for transportation on land. A characteristic feature of hybrid vehicles is that they have both an internal combustion engine and at least one electric machine as drive aggregates.
The electric machine is usually operated at an inverter, which enables an electric coupling between an accumulator of the hybrid vehicle and the electric machine. For this purpose the accumulator provides an intermediate circuit or is connected to such an intermediate circuit to which also the inverter for the electric machine is connected. In this way the electric coupling between the electric machine and the accumulator is accomplished. The intermediate circuit is usually configured as direct voltage intermediate circuit.
In vehicles of the general type, internal combustion engines can usually be coupled with the drive axle of the vehicle via a mechanical clutch, so as to enable starting up and also shifting procedures during normal operation. Such a clutch is usually provided for the internal combustion engine also in hybrid vehicles to enable reliable starting up independent of the operational readiness of the electric machine. In conventional non-hybrid vehicles this function is strictly required for proper operation.
The mechanical clutch in motor vehicles is a device that is subject to wear and besides being a cost factor in and of itself requires maintenance work.